Aluminum or Aluminium? Whats the difference................?

Why two spellings?

Following up a Topical Words piece on the international spelling of what British English writes as sulphur, many American subscribers wrote in to ask about another element with two spellings: aluminium.

The metal was named by the English chemist Sir Humphry Davy (who, you may recall, “abominated gravy, and lived in the odium of having discovered sodium”), even though he was unable to isolate it: that took another two decades’ work by others. He derived the name from the mineral called alumina, which itself had only been named in English by the chemist Joseph Black in 1790. Black took it from the French, who had based it on alum, a white mineral that had been used since ancient times for dyeing and tanning, among other things. Chemically, this is potassium aluminium sulphate (a name which gives me two further opportunities to parade my British spellings of chemical names).

Sir Humphry made a bit of a mess of naming this new element, at first spelling it alumium (this was in 1807) then changing it to aluminum, and finally settling on aluminium in 1812. His classically educated scientific colleagues preferred aluminium right from the start, because it had more of a classical ring, and chimed harmoniously with many other elements whose names ended in –ium, like potassium, sodium, and magnesium, all of which had been named by Davy.

The spelling in –um continued in occasional use in Britain for a while, though that in –ium soon predominated. In the USA, the position was more complicated. Noah Webster’s Dictionary of 1828 has only aluminum, though the standard spelling among US chemists throughout most of the nineteenth century was aluminium; it was the preferred version in The Century Dictionary of 1889 and is the only spelling given in the Webster Unabridged Dictionary of 1913. Searches in an archive of American newspapers show a most interesting shift. Up to the 1890s, both spellings appear in rough parity, though with the –ium version slightly the more common, but after about 1895 that reverses quite substantially, with the decade starting in 1900 having the –um spelling about twice as common as the alternative; in the following decade the –ium spelling crashes to a few hundred compared to half a million examples of –um.

Actually, neither version was often encountered early on: up to about 1855 it had only ever been made in pinhead quantities because it was so hard to extract from its ores; a new French process that involved liquid sodium improved on that to the extent that Emperor Napoleon III had some aluminium cutlery made for state banquets, but it still cost much more than gold. When the statue of Eros in Piccadilly Circus in London was cast from aluminium in 1893 it was still an exotic and expensive choice. This changed only when a way of extracting the metal using cheap hydroelectricity was developed.

It’s clear that the shift in the USA from –ium to –um took place progressively over a period starting in about 1895, when the metal began to be widely available and the word started to be needed in popular writing. It is easy to imagine journalists turning for confirmation to Webster’s Dictionary, still the most influential work at that time, and adopting its spelling. The official change in the US to the –um spelling happened quite late: the American Chemical Society only adopted it in 1925, though this was clearly in response to the popular shift that had already taken place. The International Union of Pure and Applied Chemistry (IUPAC) officially standardised on aluminium in 1990, though this has done nothing, of course, to change the way people in the US spell it for day to day purposes.

It’s a word that demonstrates the often tangled and subtle nature of word history, and how a simple statement about differences in spelling can cover a complicated story.